Aluminium oxide is impermeable and, unlike the oxide layers on many other metals, it adheres strongly to the parent metal. If damaged mechanically, aluminiumâs oxide layer repairs itself immediately.
Saliva helps remove oral waste and cavity-causing bacteria, protects teeth from decay by neutralizing harmful acids, and helps re-mineralize tooth enamel. Saliva also keeps oral tissues healthy by preventing infection by controlling bacteria and fungi in the mouth.
Salivary gland problems. The glands producing saliva in the mouth can develop problems, including becoming swollen, infected, or can develop cysts or deposits called stones. Your salivary glands produce nearly a litre of saliva each day. Saliva is important to lubricate your mouth, help with swallowing, protect your teeth against bacteria, and aid in the digestion of food. The three major pairs of salivary glands are: Parotid glands on the sides of the face.